Methods of identifying and/or assessing cardiac arrhythmias using an implantable medical device

Abstract

Apparatus using one or more modes of statistical analysis with one or more monitored parameters of a patient's heart to identify and/or assess arrhythmias. Through use of the one or more modes of statistical analysis, a medical professional can be aided during evaluation of patient data for diagnosis of the patient. At least one of the monitored parameters may include one or more values used representatively for storage intervals of a selected length. As such, for each storage interval, a value may be determined for the one monitored parameter occurring at an upper percentile and a lower percentile. In addition, a median value may be determined for the one monitored parameter for each storage interval. Over a plurality of the storage intervals, these determined values can be used in one or more modes of statistical analysis to better identify and assess the arrhythmias.

The invention claimed is: 
     
       1. A non-transitory computer-readable medium programmed with instructions for performing a method of identifying and/or assessing patient arrhythmias, the medium comprising instructions for causing a programmable processor to:
 obtain a set of values, the values representative of a heart parameter of a patient collected over successive time intervals, the set gathered from a memory of a medical device implanted within the patient, 
 process the set of values to identify values that exceed a predetermined amplitude threshold value, such identified values thereby meeting a first criterion; 
 for each identified value, compare the identified value with the value from a preceding time interval to determine if such identified value exceeds the preceding time interval value by a difference threshold amount, such identified value thereby meeting a second criterion; and 
 provide an indication of presence of an arrhythmia for storage intervals having values in which the first and second criteria are met. 
 
     
     
       2. The computer readable medium of  claim 1 , wherein the heart parameter comprises heart rate. 
     
     
       3. The computer readable medium of  claim 1 , wherein each value is representative of one of a statistically high, medium, and low measure of the heart parameter collected over a respective time interval. 
     
     
       4. The computer readable medium of  claim 1 , wherein each value is representative of a predetermined percentile measure of the heart parameter collected over a respective time interval. 
     
     
       5. The computer readable medium of  claim 1 , wherein the successive time intervals encompassed by the set of values extend over a predetermined amount of time. 
     
     
       6. The computer readable medium of  claim 1 , wherein the preceding time interval is the time interval immediately preceding that of the identified value. 
     
     
       7. The computer readable medium of  claim 1 , wherein the preceding time interval is one of the first, second, and third time intervals immediately preceding that of the identified value. 
     
     
       8. The computer readable medium of  claim 1 , wherein the preceding time interval includes the first, second, and third time intervals immediately preceding that of the identified value. 
     
     
       9. The computer readable medium of  claim 1 , wherein the predetermined amplitude threshold value comprises a value for the heart parameter indicative of an arrhythmia. 
     
     
       10. The computer readable medium of  claim 1 , wherein the difference threshold amount comprises a difference between the heart parameter during an arrhythmia and the heart parameter prior to an arrhythmia generally corresponding to onset of an arrhythmia.